Field of the Disclosure
The present application relates to an organic light emitting diode display device and a fabricating method thereof. More particularly, the present application relates to an organic light emitting diode display device and a fabricating method thereof adapted to enhance an output efficiency of light in a perpendicular direction.
Description of the Related Art
Nowadays, a display field for visually representing an electrical information signal has been rapidly developed with the spread of information society. In accordance therewith, a variety of flat panel display devices with features, such as slimness, light weight and low power consumption have been developed. Also, the flat panel display devices have been rapidly replacing the existing cathode ray tubes (CRTs).
As examples of the flat panel display devices, liquid crystal display (LCD) devices, organic light emitting diode (OLED) display devices, electrophoretic display (electric paper display (EPD)) devices, plasma display panel (PDP) devices, field emission display (FED) devices, electroluminescence display (ELD) devices, elector-wetting display (EWD) devices, and so on can be introduced. Such flat panel display devices commonly include a flat display panel, which realizes an image, as a necessary component. The flat display panel is configured with a pair of combined substrates which face each other with having an inherent light emitting or polarizing material layer therebetween.
The OLED display device belonging to such flat panel display devices corresponds to a self-luminous device. Such an OLED display device does not require a separate light source which is used in the LCD device being a non-luminous device. As such, the OLED display device can become lighter and thinner. Also, the OLED display device has a wider viewing angle, a higher contrast ratio, lower power consumption and lower DC (direct current) voltage drive and a faster response speed, compared to the LCD device. Moreover, the OLED display device endures external impacts and is used in a wide temperature range because of having solidified internal components.
In the OLED display device, light emitted from an organic light emitting element must pass through a plurality of layers when being output to the exterior along a perpendicular direction. Then, a total reflection phenomenon is caused by reflectance differences between the plurality of layers. Due to this, light leaks in lateral directions. In view of this point, it is necessary to enhance an output efficiency of light in the perpendicular direction.